The St. John’s locker room in the Garden was a madhouse. There was clapping and shouting. MP3 players or cell phones were pressed to player’s ears.

Center Abe Keita, the emotional trigger of this team, bellowed out congratulations to the coaching staff, the starters, the subs, even the walk-ons. Then Andre Stanley, the captain and a former walk-on himself, took it upon himself to remind his St. John’s teammates that one win isn’t what it’s all about.

“I told them it was great to be happy, but to act like we’ve been here before,” said Stanley. “We are St. John’s after all. We should expect to win.”

There was no reason to expect a St. John’s win, no less a 71-55 blowout of UCLA, but after seven straight losses the Red Storm came together yesterday to form the perfect storm. With 17.5 seconds left, interim head coach Kevin Clark called timeout to empty the bench.

“It is nice that they can smile,” said Clark. “I think they walked out every time [after losses] with their heads held high but I am sure they will have more friends today.”

Walk-on Joe McDonald capped the euphoria by swishing a 3-pointer from right in front of the Red Storm bench to set off a wild celebration. Keita danced around at center court. Freshman Lamont Hamilton waved a towel over his head.

“This win was something we all needed,” said McDonald. “These guys work so hard in practice and we got so close so many times, to finally get that win, it was just great to see everyone happy.”

For the first time since Jan. 3, St. John’s (5-13) is happy. UCLA (9-8), now losers of five straight, is the storied program in a freefall. The Bruins were outrebounded 49-30 and missed 11 of 15 foul shots.

“You have to give St. John’s credit,” said first-year UCLA coach Ben Howland. “With the season they’ve had with four wins, they came in here with some fire and they took it right to us and beat us soundly on national television.”

Yes, CBS was in the house wondering how St. John’s-UCLA had turned into a matchup of teams that had lost a combined 11 straight. But the Red Storm, didn’t look anything like the squad that had lost seven straight Big East games.

Ingram, who had become so disheartened by the losing that he said he’ll address his future at St. John’s after the season, drained 5-of-10 treys in the first half as the Red Storm took a 41-24 lead. Senior Kyle Cuffe had a career-high 15 rebounds to go with 13 points.

Curtis Johnson, who hasn’t played since Dec. 6 against Duke, got two rebounds and one blocked shot in the first half. Stanley had eight points, nine boards and three assists as St. John’s ended its longest losing streak in 85 years.

“We were always knocking on the door,” said Stanley. “Every game we were right there. We were just waiting to bust through the door and hopefully this is it.”